谐波增强与频率估计的自适应方法

THE ADAPTIVE METHOD OF HARMONIC SIGNAL ENHANCEMENT AND FREQUENCY ESTIMENT

基于递归预测误差原理，研究了用来估计谐波中基波频率和增强谐波的方法，并由此设计了一种具有任意的窄带性能和预期形状的均匀切口的自适应谐波增强或陷波滤波器．由于算法非线性部分只涉及基波频率一个参数，使算法很易用于具有高次谐波的过程．而且由于利用了可变极点半径和忘却因子（ｆｏｒ－ｇｅｔｔｉｎｇｆａｃｔｏｒ）因而算法对谐波频率的敏感性强，收敛速度快，并能跟踪频率时变的信号．

Based on recursive prediction error(RPE)method,an algorithm is developed for estimating the fundamental frequency and enhancing the harmonic component in the inputsignal.And an adaptive notch filter (ANF)has been designed, which characterized byvery narrow bandwidth and uniform notches of desired shape.The nonlinear part of the algorithm involves only one parameter-the signal fundamental frequency,this enables the algorithm to be worked with significantly large orderharmonic signals. Being used time-varying pole modulus and forgetting factor in GaussNewton search direction,the algrithm improves the sensitivity in the presence of harmonics and increases its convergente rate,and can also be used with frequency trackingof time-varying frequency signals.